“Although this could one day lead to a pre-natal test for male sexual orientation, it would not be very accurate, as there are other factors that can influence the outcome.’”
So it is caused by genes but it isn’t really because there are other factors at play, but these factors, by fiat, can’t be anything remotely similar to choices made.
It’s blather.
As far as the actual genetic findings, the article is not published yet.
Schizophrenia is a genetic condition, yet many individuals with the genes that cause it never develop it. That is because gene expression is influenced by environment. Geneticists talk about traits being n% caused by genetics and (100 - n)% caused by environment, because almost all genetic conditions have an environmental component. The "environment" can be a range of factors--an infectious disease, exposure to a noxious chemical, suboptimal conditions during birth, etc.